John,

Glad ot hear you've joined the W-116 300SD rank! I have an '80 SD which I absolutely love. As far as your questions, I'll do my best to clear them up for you..

They are naturally a little sluggish off the line until the boost comes in (around 2,200rpm). You might want them to check pump timing which would help in acceleration, and they can richen the fuel injection, but that will of course lead to more noticeable tailpipe emissions. About the buzzing, that is normal. Don't worry about it. The electric cooling fan forward of the radiator will come on when the engine reaches a certain temperature. If you're sitting in traffic for a while in hot weather, you'll probably notice it coming on. Check that the fan operates freely. If not, then the fan is locked up and you'll have to get a new one. Also, if the fan is indeed locked up, then don't run the A/C until you correct the problem. As with the driveline vibration, they all seem to have a slight vibration, but it can't hurt to have the driveshaft checked. Cruise control: If it works intermittently, you'll have to determine whether the switch, amplifier or actuator is going bad. There is a tester made to check the switch, and any good MB shop should have one in their special tool arsenal. If the cruise picks up when you lift the switch but won't hold, then the amp is bad. They run around $180 or so rebuilt with an $80 core charge. What kind of tires did you have put on the car? I have Michelin Energy MXV4s on mine and they're terriffic. The next best tire in my opinion would be the Pirelli P4000 Super Touring. A little noisier than the MVX4, but a heck of alot cheaper! I think they're about $54 each for the Pirelli versus $94 each for the Michelin. Ok, hope this helps!


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Rgds,
Aaron Greenberg
MB technician
Precision Motorcars, Cincinnati, Ohio
'67 250SE Cabriolet
'77 450SL
'79 6.9 (SOLD)
'80 300SD
'85 380SE
'89 420SEL
'93 300E 2.8